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View Full Version : I screwed up and need some help - Bench Top Buildup



Patrick F Graham
08-23-2021, 2:41 PM
I'll just go ahead and admit it - super stupid move on my part.

Project Setup:
Building a Roubo Split Top bench, my first real bench in my life (57 years old, working with wood since at 13 in boarding school).

It's not an exact Benchcrafted version but that's not important right now (but I am using one of their Acme Screw kits - NOT in love but another story later).

I'm doing it with a HomeDepot 2x6 build up, 3-3/4" thick top, slightly dressed 2x6's to get something close to square, etc., etc. (mostly I'm doing it this way to understand the entire process so I can build a better one at another time).

So, to make top align (flat), I put #20 biscuits every 12-15" down the 6' cut board. Quick picture of last night's glue up here>
463493

So, I had to adjust the biscuit jointer to a shorter distance from the referenced top down to accommodate the thinner space near the area around the end-vice cutouts to 3/4" then back to 1" for the other 10 or so slots - 5 each.

Here's my steps, should be easy to see my HUGE dumb move:
- Using my existing 1" biscuit jointers settings, I put all 5 slots on the glued-up bench top
- Adjusted the biscuit jointer to 3/4" and slotted the 1 spot that couldn't take the 1"-er.
- Took my next piece to add to the top (shown in the pic as the top of the stack), remembering I adjusted to 3/4", I adjusted back to 1" and slotted my to my corresponding locations
- Changed the biscuit jointer to 3/4" then did the slot for that singe one.

At this point the damage is done - can you see it?

- Did the glue up, added all the clamps etc. etc., time, etc.....

The mistake is, I touched the stupid biscuit jointers height adjustment BETWEEN one side and the other - TWICE!!!!

So, now I have a slightly, 32'nd +/- board sticking up and still need to add one more board to it.

Considering each of the '2x6's are cut down exact finished height, I can't, and don't know how I can thickness plane my way out of this screw up AND don't know how to fix it so I can accurately add my last board to this 'half' of my Split Half bench top.

Any ideas about how to fix this dumb move? The bottom is to uneven to simply run through the plainer - maybe a 'carrier' for the whole section then through the plainer - I don't know - so mad at myself.

Thanks, Patrick

Paul F Franklin
08-23-2021, 3:02 PM
Patrick, if this is your worse goof...well, I'd wager you have something else to look forward to cause we've all been there.:)

I'd say either mount it to a sled, shimming as needed, and run it through your planer, or rig up a flattening jig for the router, like folks use to flatten large slabs. Either way, I'd probably attach the last board before the flattening step. You only need to get it close (aim to have it a tad high) because it will get leveled to the others in the flattening step.

Of course, if you have hand plane skills, you could go that route; most folks do a final flattening with a hand plane anyway once all is mounted and done.

For the future, one way to avoid having to muck with the setting on the biscuit joiner is to leave it set at 1" and use a 1/4" spacer under the fence when you need 3/4.

Steve Fish
08-23-2021, 3:22 PM
I admit I have never built one of these benches so I’m not sure if this will work for you. Plane it upside down on a sled with the offending board off the edge of the sled, flip it and then do the top.

Patrick F Graham
08-23-2021, 3:26 PM
Photo with clamps off - light from garage door coming in from right of photo exaggerates the screw up but illustrates it for clatiety.
463503

Damn, I'm so mad at myself!

Patrick F Graham
08-23-2021, 3:38 PM
As I mentioned Steve, I've left the bottom to be whatever to deal with or not later so, I have NO flat surface to reference to - Paul's idea of a sled is maybe the only big picture fix.

I don't know, thinking, thinking...

Patrick

Patrick F Graham
08-23-2021, 3:44 PM
Electric hand plane????

I don't have one, haven't for years, used them a lot for hanging doors.

I remember then to be LOUD and rather unforgiving if not set up right.

Maybe???

Mikita KP0800K 3-1/4" Planer - ~$170 ? ? ?

Patrick

Steve Fish
08-23-2021, 4:05 PM
I was in agreement with Paul about using a sled. I was maybe not explaining it well. If you fix the bottom first you can then use it to reference from to fix the top using your planer. Or do you not have a planer?
edit; of course you do, I see a nice Jet unit in your last picture. This video is somewhat close to what I was suggesting. Your evenly glued boards would be substituted for the partially jointed board
https://www.youtube.com/watch?v=vzmSjlXJ2fg

Bryan Lisowski
08-23-2021, 4:36 PM
Couple questions. 1) is this the bottom? 2) is the other side flat? If the answers to both are yes, you could pour epoxy along the mess up. Then you can sand or send through the planer. I had this happen when I glued mine up, partly because I didn’t use biscuits or dominos, so I got some creep. With the epoxy being on the bottom nobody will see.

Mike Rambour
08-23-2021, 4:50 PM
Its only a little bit that you have work with, I would make up a slab flattening jig and hit it with that. I know you said the boards are already at finished dimension but I would make a new finish dimension and flatten it.

Scott Winners
08-23-2021, 5:15 PM
I think I wound put the last board on, positioned so the bottom of the bench will be as flat as possible. You will have a little valley in the bottom however deep, but other wise "flat" all the way round the perimeter and most of the field.

Then you could run it through your thickness planer bottom side down to flatten the top, and then if you must (I don't know your undercarriage joinery) flip the slab again and flatten the bottom.

The "flaw" you have pictured is pretty minor as bench tops go. With a properly tuned scrub plane that would be a ten minute job. Buying a plane and then turning it into a scrub plane and the tuning it as a scrub plane; use the power planer your got, it will be faster and less work. I see being able to run the two slabs through a thickness planer as one very attractive element of the split top design.

Derek Cohen
08-23-2021, 8:01 PM
Patrick, a hand plane would take that down in a few minutes. A Stanley #5 is designed to do this.

Regards from Perth

Derek

Richard Coers
08-23-2021, 9:00 PM
Personally, I think your first screw up was buying Home Depot 2x6s. With recent prices you could have purchased hard maple from a lumber dealer for less money. But most importantly, you would have material dried to 6-8% instead of 19+%. I'm working on the bench I made 40 years ago.
463529

Myk Rian
08-23-2021, 9:32 PM
Run the top over the table saw and cut the board off. Then redo it.

John Kananis
08-23-2021, 9:47 PM
I agree with those that said use a hand plane (#5, #7, take your pick). That's really not bad at all and don't worry about the lost thickness, 3.5" is very substantial - if anything, hold fasts will sometimes hold better on less than 3.5 inches.

Patrick F Graham
08-24-2021, 7:37 PM
Alright - this site is AMAZING!

I took a couple bits from Paul, Mike, Scott, Derek, etc.

So, what I took was to get back to flat then deal with the 'bump'.

This is a picture of the benchtop on it's side, illustrating the problem and the 'fix'.
463579

I decided to use my biscuit jointer set at 1" depth and cut slots on the glued-up portion of the benchtop, offset the next board to be below the mistake by exactly the same amount then run it through my Jet 13" planer or use a hand plane (#5, #6, etc.) to flatten out the bump.

Steps:
- After getting over the fear and reading everything you guys contributed, I reset my Dewalt biscuit jointer (not a particularly precise tool, sadly) to 1" > doesn't matter what I set it to since it's going to work with the new dimensioned 2x6 to be added.

- I slotted the glued-up side first - all the way.

- Then, I took a sharp scrap (fully square) and made the same slot on one end > picture
463580
Marked from L to R - Test #3, Test #2, Test #1, Matching

- I started adjusting the biscuit jointer (in my case down) shallower then mad a test slot, add a biscuit and test it against the glued-up benchtop using a killer Skarrett 6" Double (first time I EVER measured in 64ths).

- Once I got it, 3rd try - I cut corresponding slots on the new board. The mistake was 5/64ths.

- Glue up - L to R - Top, Bottom
463581 463582

The first picture at the top is what's in the clamps now - pretty darn (I hate the word, but....) close.

I'll pop the clamps around 6 tonight (PST) - 5 hrs of cure time, see how she looks.

Then, taking more advice, I'll give up on target dimension thickness and see if I can run it through the planer bottom side down first to remove the mistake. Maybe one tiny pass flipped, maybe, just to clean it up, or wait to add my last board for this section of the bench top.

I'll post the after clamp pictures and post planer pics tonight.

QUICK NOTE on why the thickness is important - I bought the Benchcrafted tail vice and it's SOOOOOO complicated to install - overly complicated (more at another time, another thread). The key dimension among all the the key must not change dimensions is the thickness of the base. Anyway, I know why they want it that way and stuff like that.....

- Patrick

Patrick F Graham
08-24-2021, 7:48 PM
Come on man, don't poop on medium to inadequate, never fully dimensioned to spec, twisted, cupped, warped, knotted beyond the legal limit, poorly stacked, dregs of dregs, wet, lumber - that's just mean and I think uncalled for!

Did I mention the cashier in the Pro area, Patty, has two almost adult sons and is cute as a little cupcake - I'm not sure what that has to do with the quality of the lumber but it sure makes me happy(er) come check-out time.

Seriously, like, not love your bench. Mines going to be closer to that then the Split version from Benchrafted. I don't like the full Tail Vice, I'm going for the 'wagon wheel end vice' version:
463585

Once I get past this stupid mistake, I'll do a stacked photo to illustrate what mine's going to look like.

Cool bench Richard!

- Patrick

Patrick F Graham
08-24-2021, 9:16 PM
Alright - this site is AMAZING!

I took a couple bits from Paul, Mike, Scott, Derek, etc.

So, what I took was to get back to flat then deal with the 'bump'.

This is a picture of the benchtop on it's side, illustrating the problem and the 'fix'.
https://sawmillcreek.org/attachment.php?attachmentid=463579&d=1629846398&thumb=1 (https://sawmillcreek.org/attachment.php?attachmentid=463579&d=1629846398)

I decided to use my biscuit jointer set at 1" depth and cut slots on the glued-up portion of the benchtop, offset the next board to be below the mistake by exactly the same amount then run it through my Jet 13" planer or use a hand plane (#5, #6, etc.) to flatten out the bump.

Steps:
- After getting over the fear and reading everything you guys contributed, I reset my Dewalt biscuit jointer (not a particularly precise tool, sadly) to 1" > doesn't matter what I set it to since it's going to work with the new dimensioned 2x6 to be added.

- I slotted the glued-up side first - all the way.

- Then, I took a sharp scrap (fully square) and made the same slot on one end > picture
https://sawmillcreek.org/attachment.php?attachmentid=463580&d=1629847030&thumb=1 (https://sawmillcreek.org/attachment.php?attachmentid=463580&d=1629847030)
Marked from L to R - Test #3, Test #2, Test #1, Matching

- I started adjusting the biscuit jointer (in my case down) shallower then mad a test slot, add a biscuit and test it against the glued-up benchtop using a killer Skarrett 6" Double (first time I EVER measured in 64ths).

- Once I got it, 3rd try - I cut corresponding slots on the new board. The mistake was 5/64ths.

- Glue up - L to R - Top, Bottom
https://sawmillcreek.org/attachment.php?attachmentid=463581&d=1629847595&thumb=1 (https://sawmillcreek.org/attachment.php?attachmentid=463581&d=1629847595) https://sawmillcreek.org/attachment.php?attachmentid=463582&d=1629847638&thumb=1 (https://sawmillcreek.org/attachment.php?attachmentid=463582&d=1629847638)

The first picture at the top is what's in the clamps now - pretty darn (I hate the word, but....) close.

I'll pop the clamps around 6 tonight (PST) - 5 hrs of cure time, see how she looks.

Then, taking more advice, I'll give up on target dimension thickness and see if I can run it through the planer bottom side down first to remove the mistake. Maybe one tiny pass flipped, maybe, just to clean it up, or wait to add my last board for this section of the bench top.

I'll post the after clamp pictures and post planer pics tonight.

QUICK NOTE on why the thickness is important - I bought the Benchcrafted tail vice and it's SOOOOOO complicated to install - overly complicated (more at another time, another thread). The key dimension among all the the key must not change dimensions is the thickness of the base. Anyway, I know why they want it that way and stuff like that.....

- Patrick

Scott Winners
08-24-2021, 10:35 PM
Looks like you are winning Patrick. No question you will flatten the bench top before it goes into service.

You don't necessarily have to flatten the bottom. All the wood you can leave on the underside of the bench top will contribute to the bench's final working weight. At six feet length even with SPF(s) construction lumber for the top, 3 inch thickness will be enough total bench mass for all but the most unusual and violent bench operations.

I would urge extreme caution and measure two or three times before deciding whether or not to shim the bottom before you apply your thickness planer to the top surface. Maybe even leqave it in the clamps overnight tonight (I might be too late with this idea given it is nearly 730PM for you as I type...

What are your two slabs going to rest on? Is that little valley on the underside, the valley of the "DA river" goign to make a hill of beans difference in the final, finished bench if you don't flatten it out?

Patrick F Graham
08-24-2021, 11:35 PM
Haven't popped the clamps yet, been working on stupid stuff at work and trying to get a date on Match (equally like work, if truth be known...).

I know the underside can be left alone, I was mentioning it because I thought once I have the bottom flat and somewhat perpendicular to one of the sides, I could reference that side down to get a smooth top side - no other reason.

I'm not sure what I'm going to do with the bottom but I'll probably make something simple for now. The driving reason I built my first bench this far down the line (age, experience, could always make due, allergic to hand tools for the longest time, etc.) is I need to do two cuts for a series of reproduction Morris Drop Arm Spindale Reclining Chairs - (Model 360) and the back slats need these two cuts:
463595 463596 463597

So, no manly #8 planing of 24" wide barn recovered planks needed - saw horses - something - for now.

I was thinking about plowing a 2 - 2" wide by 3/4" deep rabbit running front to back on the bottom to give me an even spot to rest it on.

Time to pop those clamps.....

John Kananis
08-25-2021, 8:38 AM
Looking good, Patrick. A trick you may want to consider to increase the accuracy of you biscuit joiner is to bolt it down on a sheet good and bring the work to the machine instead of the reverse.

Patrick F Graham
08-25-2021, 12:29 PM
After releasing the clamps last night, this:
463616

I'm pretty happy with the 'fix'.

After thinking about it, decided NOT to run it through the planer - instead, waiting to glue up final board to the slab then consider my flattening options.

Probably get second slab started then when done, run them both through achieve two matching slabs.

Here's the glue-up of the final board from last night - god knows why anyone would want to see one more picture of my slow stacking game, but here it is:
463620 Hummm, reminds me of.....

463621

C A K E !


- Patrick

Patrick F Graham
08-25-2021, 12:32 PM
Wait a second, are you reading my mind - what the !

Makes me crazy why it isn't more accurate - [B]PLEASE explain, anything to make it dead-on would be tremendous.

Thanks, can't wait.